1. Field of the Invention
The invention relates to electric lamps and particularly to electric lamps. More particularly the invention is concerned with lamps with a plurality of enclosed filaments.
2. Description of the Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Advanced forward lighting headlamp systems (AFS) are being developed to light the road on the side a vehicle is turning to. The first AFS headlamp systems used one lamp and one reflector or projector lens. The beam control was achieved by rotating the entire lamp to the right or left with a stepper motor. This is a mechanically complex and expensive system. Alternative systems were devised using a first lamp to generate a forward beam and a second lamp to generate an augmenting side beam in response to a turning signal. By tuning between the two sources one can aim the beam. The two lamp AFS systems may use either or both two light sources, and two reflectors. The cost of the extra material for the lamps and the reflectors, the space and volume for the second lamp, and the additional labor in mounting, and aiming the duplicative systems makes the enhanced lighting system expensive.